Screening for depression in high-risk patients is not effective
A primary care study has found that only 1% of patients in high-risk groups who were invited for screening received treatment for major depression as a result.
A prospective cohort study was carried out in three health centres in the Netherlands. Three high-risk groups were chosen: patients who had been seen with a new mental health problem within the previous three months, patients who had been seen with persistent (>90 days) medically unexplained symptoms (MUSs) within the previous four weeks, and the top 10% of frequent attenders. The prevalence of depression in this group of patients was expected to be 2-3 times the prevalence in unselected primary care patients.
In all, 2005 patients were identified, comprising 970 with mental health problems, 107 with MUSs and 1,258 frequent attenders. Of these, 311 patients qualified for two or three of the high-risk groups. A total of 318 patients were excluded from screening, the most common reason was that they had already been given a diagnosis of major depression.
Patients were sent an invitation letter together with a PHQ screen. Those with a PHQ-9 score ? 10 were assessed for major depression using a semi-structured telephone interview.
Of the 1,687 patients invited for screening, 780 participated and 71 were diagnosed with major depression. Of these, 36 were already receiving treatment, 14 refused treatment and 4 did not attend their appointment. Thus 17 patients (1% of 1,687) accepted treatment for their depression.
Before the introduction of the QOF, we investigated the value of screening our CHD patients using the HADS questionnaire. Of 93 patients screened, 37 had a depression score ? 8, eight were lost to follow-up, 12 were not considered by our nurse to have major depression and two were already receiving antidepressant treatment. Seven patients did not wish antidepressant treatment and declined a GP appointment. Thus, eight were referred to a GP, of whom four were commenced on treatment for unrecognised depression.
Our number needed to screen was better than for this study (23 as compared with 46). Nevertheless, we also concluded that the low treatment initiation rate did not justify the time and effort involved. One of the difficulties is that patients are often unwilling to accept treatment for depression identified by screening: just under half of the patients identified by the Dutch study (17/35) accepted treatment and just over half of the patients that our nurse thought were suffering from depression accepted the recommendation of an appointment with their GP (8/15).
Screening for depression in high-risk patients does not appear to be effective and has diverted attention from the need to provide more effective care to patients with recognised depression.1
Baas KD, Wittkampf KA, van Weert HC et al. Screening for depression in high-risk groups: prospective cohort study in general practice. Br J Psych 2009; 194:399-403